407 CO2 pollution
Few people realize how much air is polluted by cars. This exhibit
demonstrates how much air is being polluted, by the cars, over a city
every year. There are three handles with labels (only one is shown in
the sketch) , and the visitor selects one. When pulling in the
correct one, the corresponding volume of air will be contained in a
raising box over the city map. It turns out to be in a volume that
covers the city up to 5 km's height.